blah2/lib/asio-1.26.0/asio/co_spawn.hpp
2023-05-04 20:55:37 +09:30

523 lines
16 KiB
C++

//
// co_spawn.hpp
// ~~~~~~~~~~~~
//
// Copyright (c) 2003-2022 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#ifndef ASIO_CO_SPAWN_HPP
#define ASIO_CO_SPAWN_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include "asio/detail/config.hpp"
#if defined(ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
#include "asio/awaitable.hpp"
#include "asio/execution/executor.hpp"
#include "asio/execution_context.hpp"
#include "asio/is_executor.hpp"
#include "asio/detail/push_options.hpp"
namespace asio {
namespace detail {
template <typename T>
struct awaitable_signature;
template <typename T, typename Executor>
struct awaitable_signature<awaitable<T, Executor>>
{
typedef void type(std::exception_ptr, T);
};
template <typename Executor>
struct awaitable_signature<awaitable<void, Executor>>
{
typedef void type(std::exception_ptr);
};
} // namespace detail
/// Spawn a new coroutined-based thread of execution.
/**
* @param ex The executor that will be used to schedule the new thread of
* execution.
*
* @param a The asio::awaitable object that is the result of calling the
* coroutine's entry point function.
*
* @param token The @ref completion_token that will handle the notification that
* the thread of execution has completed. The function signature of the
* completion handler must be:
* @code void handler(std::exception_ptr, T); @endcode
*
* @par Completion Signature
* @code void(std::exception_ptr, T) @endcode
*
* @par Example
* @code
* asio::awaitable<std::size_t> echo(tcp::socket socket)
* {
* std::size_t bytes_transferred = 0;
*
* try
* {
* char data[1024];
* for (;;)
* {
* std::size_t n = co_await socket.async_read_some(
* asio::buffer(data), asio::use_awaitable);
*
* co_await asio::async_write(socket,
* asio::buffer(data, n), asio::use_awaitable);
*
* bytes_transferred += n;
* }
* }
* catch (const std::exception&)
* {
* }
*
* co_return bytes_transferred;
* }
*
* // ...
*
* asio::co_spawn(my_executor,
* echo(std::move(my_tcp_socket)),
* [](std::exception_ptr e, std::size_t n)
* {
* std::cout << "transferred " << n << "\n";
* });
* @endcode
*
* @par Per-Operation Cancellation
* The new thread of execution is created with a cancellation state that
* supports @c cancellation_type::terminal values only. To change the
* cancellation state, call asio::this_coro::reset_cancellation_state.
*/
template <typename Executor, typename T, typename AwaitableExecutor,
ASIO_COMPLETION_TOKEN_FOR(
void(std::exception_ptr, T)) CompletionToken
ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
inline ASIO_INITFN_AUTO_RESULT_TYPE(
CompletionToken, void(std::exception_ptr, T))
co_spawn(const Executor& ex, awaitable<T, AwaitableExecutor> a,
CompletionToken&& token
ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
typename constraint<
(is_executor<Executor>::value || execution::is_executor<Executor>::value)
&& is_convertible<Executor, AwaitableExecutor>::value
>::type = 0);
/// Spawn a new coroutined-based thread of execution.
/**
* @param ex The executor that will be used to schedule the new thread of
* execution.
*
* @param a The asio::awaitable object that is the result of calling the
* coroutine's entry point function.
*
* @param token The @ref completion_token that will handle the notification that
* the thread of execution has completed. The function signature of the
* completion handler must be:
* @code void handler(std::exception_ptr); @endcode
*
* @par Completion Signature
* @code void(std::exception_ptr) @endcode
*
* @par Example
* @code
* asio::awaitable<void> echo(tcp::socket socket)
* {
* try
* {
* char data[1024];
* for (;;)
* {
* std::size_t n = co_await socket.async_read_some(
* asio::buffer(data), asio::use_awaitable);
*
* co_await asio::async_write(socket,
* asio::buffer(data, n), asio::use_awaitable);
* }
* }
* catch (const std::exception& e)
* {
* std::cerr << "Exception: " << e.what() << "\n";
* }
* }
*
* // ...
*
* asio::co_spawn(my_executor,
* echo(std::move(my_tcp_socket)),
* asio::detached);
* @endcode
*
* @par Per-Operation Cancellation
* The new thread of execution is created with a cancellation state that
* supports @c cancellation_type::terminal values only. To change the
* cancellation state, call asio::this_coro::reset_cancellation_state.
*/
template <typename Executor, typename AwaitableExecutor,
ASIO_COMPLETION_TOKEN_FOR(
void(std::exception_ptr)) CompletionToken
ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
inline ASIO_INITFN_AUTO_RESULT_TYPE(
CompletionToken, void(std::exception_ptr))
co_spawn(const Executor& ex, awaitable<void, AwaitableExecutor> a,
CompletionToken&& token
ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
typename constraint<
(is_executor<Executor>::value || execution::is_executor<Executor>::value)
&& is_convertible<Executor, AwaitableExecutor>::value
>::type = 0);
/// Spawn a new coroutined-based thread of execution.
/**
* @param ctx An execution context that will provide the executor to be used to
* schedule the new thread of execution.
*
* @param a The asio::awaitable object that is the result of calling the
* coroutine's entry point function.
*
* @param token The @ref completion_token that will handle the notification that
* the thread of execution has completed. The function signature of the
* completion handler must be:
* @code void handler(std::exception_ptr); @endcode
*
* @par Completion Signature
* @code void(std::exception_ptr, T) @endcode
*
* @par Example
* @code
* asio::awaitable<std::size_t> echo(tcp::socket socket)
* {
* std::size_t bytes_transferred = 0;
*
* try
* {
* char data[1024];
* for (;;)
* {
* std::size_t n = co_await socket.async_read_some(
* asio::buffer(data), asio::use_awaitable);
*
* co_await asio::async_write(socket,
* asio::buffer(data, n), asio::use_awaitable);
*
* bytes_transferred += n;
* }
* }
* catch (const std::exception&)
* {
* }
*
* co_return bytes_transferred;
* }
*
* // ...
*
* asio::co_spawn(my_io_context,
* echo(std::move(my_tcp_socket)),
* [](std::exception_ptr e, std::size_t n)
* {
* std::cout << "transferred " << n << "\n";
* });
* @endcode
*
* @par Per-Operation Cancellation
* The new thread of execution is created with a cancellation state that
* supports @c cancellation_type::terminal values only. To change the
* cancellation state, call asio::this_coro::reset_cancellation_state.
*/
template <typename ExecutionContext, typename T, typename AwaitableExecutor,
ASIO_COMPLETION_TOKEN_FOR(
void(std::exception_ptr, T)) CompletionToken
ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
typename ExecutionContext::executor_type)>
inline ASIO_INITFN_AUTO_RESULT_TYPE(
CompletionToken, void(std::exception_ptr, T))
co_spawn(ExecutionContext& ctx, awaitable<T, AwaitableExecutor> a,
CompletionToken&& token
ASIO_DEFAULT_COMPLETION_TOKEN(
typename ExecutionContext::executor_type),
typename constraint<
is_convertible<ExecutionContext&, execution_context&>::value
&& is_convertible<typename ExecutionContext::executor_type,
AwaitableExecutor>::value
>::type = 0);
/// Spawn a new coroutined-based thread of execution.
/**
* @param ctx An execution context that will provide the executor to be used to
* schedule the new thread of execution.
*
* @param a The asio::awaitable object that is the result of calling the
* coroutine's entry point function.
*
* @param token The @ref completion_token that will handle the notification that
* the thread of execution has completed. The function signature of the
* completion handler must be:
* @code void handler(std::exception_ptr); @endcode
*
* @par Completion Signature
* @code void(std::exception_ptr) @endcode
*
* @par Example
* @code
* asio::awaitable<void> echo(tcp::socket socket)
* {
* try
* {
* char data[1024];
* for (;;)
* {
* std::size_t n = co_await socket.async_read_some(
* asio::buffer(data), asio::use_awaitable);
*
* co_await asio::async_write(socket,
* asio::buffer(data, n), asio::use_awaitable);
* }
* }
* catch (const std::exception& e)
* {
* std::cerr << "Exception: " << e.what() << "\n";
* }
* }
*
* // ...
*
* asio::co_spawn(my_io_context,
* echo(std::move(my_tcp_socket)),
* asio::detached);
* @endcode
*
* @par Per-Operation Cancellation
* The new thread of execution is created with a cancellation state that
* supports @c cancellation_type::terminal values only. To change the
* cancellation state, call asio::this_coro::reset_cancellation_state.
*/
template <typename ExecutionContext, typename AwaitableExecutor,
ASIO_COMPLETION_TOKEN_FOR(
void(std::exception_ptr)) CompletionToken
ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
typename ExecutionContext::executor_type)>
inline ASIO_INITFN_AUTO_RESULT_TYPE(
CompletionToken, void(std::exception_ptr))
co_spawn(ExecutionContext& ctx, awaitable<void, AwaitableExecutor> a,
CompletionToken&& token
ASIO_DEFAULT_COMPLETION_TOKEN(
typename ExecutionContext::executor_type),
typename constraint<
is_convertible<ExecutionContext&, execution_context&>::value
&& is_convertible<typename ExecutionContext::executor_type,
AwaitableExecutor>::value
>::type = 0);
/// Spawn a new coroutined-based thread of execution.
/**
* @param ex The executor that will be used to schedule the new thread of
* execution.
*
* @param f A nullary function object with a return type of the form
* @c asio::awaitable<R,E> that will be used as the coroutine's entry
* point.
*
* @param token The @ref completion_token that will handle the notification
* that the thread of execution has completed. If @c R is @c void, the function
* signature of the completion handler must be:
*
* @code void handler(std::exception_ptr); @endcode
* Otherwise, the function signature of the completion handler must be:
* @code void handler(std::exception_ptr, R); @endcode
*
* @par Completion Signature
* @code void(std::exception_ptr, R) @endcode
* where @c R is the first template argument to the @c awaitable returned by the
* supplied function object @c F:
* @code asio::awaitable<R, AwaitableExecutor> F() @endcode
*
* @par Example
* @code
* asio::awaitable<std::size_t> echo(tcp::socket socket)
* {
* std::size_t bytes_transferred = 0;
*
* try
* {
* char data[1024];
* for (;;)
* {
* std::size_t n = co_await socket.async_read_some(
* asio::buffer(data), asio::use_awaitable);
*
* co_await asio::async_write(socket,
* asio::buffer(data, n), asio::use_awaitable);
*
* bytes_transferred += n;
* }
* }
* catch (const std::exception&)
* {
* }
*
* co_return bytes_transferred;
* }
*
* // ...
*
* asio::co_spawn(my_executor,
* [socket = std::move(my_tcp_socket)]() mutable
* -> asio::awaitable<void>
* {
* try
* {
* char data[1024];
* for (;;)
* {
* std::size_t n = co_await socket.async_read_some(
* asio::buffer(data), asio::use_awaitable);
*
* co_await asio::async_write(socket,
* asio::buffer(data, n), asio::use_awaitable);
* }
* }
* catch (const std::exception& e)
* {
* std::cerr << "Exception: " << e.what() << "\n";
* }
* }, asio::detached);
* @endcode
*
* @par Per-Operation Cancellation
* The new thread of execution is created with a cancellation state that
* supports @c cancellation_type::terminal values only. To change the
* cancellation state, call asio::this_coro::reset_cancellation_state.
*/
template <typename Executor, typename F,
ASIO_COMPLETION_TOKEN_FOR(typename detail::awaitable_signature<
typename result_of<F()>::type>::type) CompletionToken
ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken,
typename detail::awaitable_signature<typename result_of<F()>::type>::type)
co_spawn(const Executor& ex, F&& f,
CompletionToken&& token
ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
typename constraint<
is_executor<Executor>::value || execution::is_executor<Executor>::value
>::type = 0);
/// Spawn a new coroutined-based thread of execution.
/**
* @param ctx An execution context that will provide the executor to be used to
* schedule the new thread of execution.
*
* @param f A nullary function object with a return type of the form
* @c asio::awaitable<R,E> that will be used as the coroutine's entry
* point.
*
* @param token The @ref completion_token that will handle the notification
* that the thread of execution has completed. If @c R is @c void, the function
* signature of the completion handler must be:
*
* @code void handler(std::exception_ptr); @endcode
* Otherwise, the function signature of the completion handler must be:
* @code void handler(std::exception_ptr, R); @endcode
*
* @par Completion Signature
* @code void(std::exception_ptr, R) @endcode
* where @c R is the first template argument to the @c awaitable returned by the
* supplied function object @c F:
* @code asio::awaitable<R, AwaitableExecutor> F() @endcode
*
* @par Example
* @code
* asio::awaitable<std::size_t> echo(tcp::socket socket)
* {
* std::size_t bytes_transferred = 0;
*
* try
* {
* char data[1024];
* for (;;)
* {
* std::size_t n = co_await socket.async_read_some(
* asio::buffer(data), asio::use_awaitable);
*
* co_await asio::async_write(socket,
* asio::buffer(data, n), asio::use_awaitable);
*
* bytes_transferred += n;
* }
* }
* catch (const std::exception&)
* {
* }
*
* co_return bytes_transferred;
* }
*
* // ...
*
* asio::co_spawn(my_io_context,
* [socket = std::move(my_tcp_socket)]() mutable
* -> asio::awaitable<void>
* {
* try
* {
* char data[1024];
* for (;;)
* {
* std::size_t n = co_await socket.async_read_some(
* asio::buffer(data), asio::use_awaitable);
*
* co_await asio::async_write(socket,
* asio::buffer(data, n), asio::use_awaitable);
* }
* }
* catch (const std::exception& e)
* {
* std::cerr << "Exception: " << e.what() << "\n";
* }
* }, asio::detached);
* @endcode
*
* @par Per-Operation Cancellation
* The new thread of execution is created with a cancellation state that
* supports @c cancellation_type::terminal values only. To change the
* cancellation state, call asio::this_coro::reset_cancellation_state.
*/
template <typename ExecutionContext, typename F,
ASIO_COMPLETION_TOKEN_FOR(typename detail::awaitable_signature<
typename result_of<F()>::type>::type) CompletionToken
ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
typename ExecutionContext::executor_type)>
ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken,
typename detail::awaitable_signature<typename result_of<F()>::type>::type)
co_spawn(ExecutionContext& ctx, F&& f,
CompletionToken&& token
ASIO_DEFAULT_COMPLETION_TOKEN(
typename ExecutionContext::executor_type),
typename constraint<
is_convertible<ExecutionContext&, execution_context&>::value
>::type = 0);
} // namespace asio
#include "asio/detail/pop_options.hpp"
#include "asio/impl/co_spawn.hpp"
#endif // defined(ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
#endif // ASIO_CO_SPAWN_HPP